The French patent applications No. 83 01742 filed on the Feb. 4, 1983, the European Pat. No. 84 400 243.6 filed on Feb. 3, 1984 and the U.S. patent application Ser. No. 591,495 filed on Mar. 20, 1984 and the inventors of which are Messrs. Johannes Andriessen and Daniel Gaillard, are incorporated in the present description by way of reference. These patent applications describe a device for supplying with power an electric receiver at variable positions on the surface, characterized in that it comprises on said surface, a network of conducting strips of the same width and spaced apart from each other, these strips being imbricated alternately in each other to form two assemblies, namely a first assembly of strips of even ranks connected to one pole of an electric power supply source and a second assembly of strips of uneven ranks connected to the other pole of the source, a variable position current sensor having at least two feelers able to contact the conducting strips and a switching circuit for supplying the receiver with power, this circuit having inputs connected respectively to the current feelers and an output connected to the receiver for supplying the receiver with power when at least two of the current feelers come into contact with two conducting strips belonging respectively to the first and second assemblies of strips connected to the two poles of the electric power source, the network of parallel conducting strips being covered with a layer of insulating material and the current feelers being in the form of metal contact needles the same length passing through the insulating material layer forming the upper covering applied to the conducting strips.
The conducting needles which are generally two or three in number and which, in this latter case are preferably disposed at the apex of an equilateral triangle may, with a suitable spatial arrangement, for example in the case where the height of the equilateral triangle is equal to the distance between the axes of the conducting strips, provide an electric connection with two adjacent conducting strips of different polarities and thus supply the receiver with power, practically for any position of the current sensor.
In accordance with the invention, the network of strips may be laid on the ground or floor and the layer of insulating material, which forms the upper covering applied to the conducting strips, may be a covering such as carpeting. In a variant, the strips may be fixed or bonded against a vertical wall and the insulating covering may be a furnishing fabric covering the wall.
This invention has great advantages to the extent that it is no longer necessary to connect a receiver which may be a domestic appliance or a lamp but also a typewriter, a computer or another office machine, to a fixed point such as a power socket.
It has however the drawback of requiring the network of conducting strips to be laid or fixed, which is an operation which must precede the hanging of the wall covering playing the role of insulating layer, and which must be carried out by staff specialized in electric installations.